The present invention relates to a method for controlling or regulating a folder of a printing press. The present invention also relates to a printing press having at least one printing unit for printing an unfolded printing material of a printed copy and having at least one folder for folding the printing material to provide the printed copy.
Folders of printing presses serve to form folds on printed printing materials. According to the prior art, a web-shaped printing material which has not yet been severed is guided through what is known as a folding former for formation of a longitudinal fold to be formed on the web-shaped printing material. Starting from the folding former, the web-shaped printing material is transported via several pull rolls in the direction of a cutting knife cylinder and a folding blade cylinder which interacts with the cutting knife cylinder. Copies are severed from the web-shaped printing material on the cutting knife cylinder and are moved in the direction of a folding jaw cylinder with the aid of the folding blade cylinder. The copy which is severed from the web-shaped printing material on the cutting knife cylinder and is moved in the direction of the folding jaw cylinder by the folding blade cylinder is transferred to the folding jaw cylinder with formation of a first crossfold by the folding blade cylinder. Further, second crossfolds may be formed between the folding jaw cylinder and a gripper cylinder which interacts with the latter. The printed copy which has been provided in this way with a longitudinal fold and crossfolds can then be provided with second longitudinal folds while still in the region of a folding table which is connected behind the gripper cylinder, the second longitudinal folds running parallel to the longitudinal fold which was formed in the folding former.
If the fold formation is to be checked according to the prior art, a folded printed copy is removed from a printing press, unfolded and examined in the unfolded state by a printer. If the printer notices here that folds run obliquely, actuators for the folding former and/or the folding blade cylinder and/or the folding jaw cylinder and/or the folding table are adjusted manually by the printer such that the desired fold is formed on subsequent printed copies. Here, the procedure is purely empirical according to the prior art, with the result that there are no reproducible results during the adjustment of the folder which is performed by the printer.